Definitions
1.nounA rope, cable etc. that holds something in place whilst allowing some movement
2.nounA strong rope or line that connects a sailor's safety harness to the boat's jackstay
3.noun(by extension) the limit of one's abilities, resources etc.
4.nounThe cardinal number three in an old counting system used in Teesdale and Swaledale. (Variant of tethera)
5.verbTo restrict something with a tether.
6.verbTo connect a cellular smartphone to another personal computer in order to give it access to a hotspot.